TerribleFire's H4 Build

[JezC]

Fair enough...any idea what the part number is (and where you got it) please?

Exxos sent me one.

He's a nice bloke - and that reminds me to check what I need for the IDE boards as well...

[terriblefire]

My H4 floppy just stopped working. I may have either knocked something or possibly powered up briefly with the TF536 and 68000 in the machine.

I'm trying to boot / use the Frontier floppy image..

https://www.frontierastro.co.uk/Files/files.html

It doesnt show the notice you usually get and goes straight to the desktop. If i click the program in auto i get Error #35.

Symptoms are that the drive clicks up to sector 170.. then 233 then the flashfloppy firmware decideds whatever has been asked for is BS and gives me a d-A on the display.

Any suggestions where to look. Could i have killed the WD1772?

(all this happens with plain 68000)

[exxos]

Sounds like a bad address, so bad bus between DMA <> 1772 ?

[terriblefire]

I found 2 pins unsoldered on the WD1772 and

HDRQ (pin 23 on the DMA)

and RESET (!) on the WD1772.

I fixed this and the behaviour is changed. Now frontier just 4 bombs and the drive head behaviour looks consistent.

EDIT: I can format a disk and I can save a newdesk.ini file on there which gets loaded. Also the AUTOBOOT.HFE loads fine. Just frontier suddenly being sulky.

[PhilC]

@terriblefire thats the same behaviour I get when trying Frontier with TF536.

Not sure if its related but a lot of the benchmarks on Gembench run really slowly with the 536 but don't on Agrandlunds 535 firmware

[terriblefire]

@terriblefire thats the same behaviour I get when trying Frontier with TF536.

Not sure if its related but a lot of the benchmarks on Gembench run really slowly with the 536 but don't on Agrandlunds 535 firmware

Found the issue. A flick of solder was bridging pins on the MMU. Looks like it came from the desoder pump when i was replacing the keyswitches on the amiga 1000.

There was a few other badly solder pins i have touched up. Fixed now.

EDIT: Also replaced the alt key and clip for it.. but managed to drop/lose one of the keycap domes... Honestly think it evapourated. Doesnt matter i guess.

[terriblefire]

Got the ROM decoder from Exxos today. Installed it worked first time.

[rubber_jonnie]

EDIT: Also replaced the alt key and clip for it.. but managed to drop/lose one of the keycap domes... Honestly think it evapourated. Doesnt matter i guess.

You may not have lost a dome, there is usually one short, have a look here: https://www.exxosforum.co.uk/forum/viewt ... t=keyboard